We hypothesize that miniature impedance sensors can be used to quantify the osseointegration of dental and other implants nondestructively in vivo, from the time of placement onward. We previously demonstrated that mechanical impedance correlates with clinical and histological measures of osseointegration. Now, we will investigate the feasibility of using semiconductor-based micro-electromechanical systems (MEMS) to construct highly miniaturized impedance instruments to be encapsulated within the implant. The devices will yield noninvasive measurements of impedance at intervals during the healing and osseointegration process. If, as we expect, these measurements correlate with established measures of integration, the instrument will give a new and improved way to observe, study, predict, and enhance the process of osseointegration. Originally targeted at dental implants, the device could be adapted to instrument other types of implants, or used as a muscle tension transducer for the treatment of neuromuscular disorders. Feasibility will be established in four tasks: (l) design and construct-a prototype from off-the-shelf components; (2) test the prototype in vitro; (3) develop a mathematical model and perform parametric analyses; and (4) develop specifications for a MEMS-based instrument. Vine Brook will collaborate with the University of Alabama at Birmingham and the University of California, Berkeley. PROPOSED COMMERCIAL APPLICATIONS: A disposable, minimally invasive instrument for continuous measurement of the mechanical impedance (rigidity) of biological structures, with applications to: progressive osseointegration of dental implants; stability of other implants and biomimetic devices; feedback of muscle tone and tension for functional electrical (neuromuscular) stimulation. Also applicable to nondestructive monitoring of the tension or stability of non- biological structures.